U.S. Pat. No. 4,405,679 to Fujioka et al discloses a coated shaped article of a polycarbonate type resin of improved abrasion resistance comprising a shaped polycarbonate substrate, an undercoat applied and cured on the substrate, and an overcoat applied and cured on the undercoat comprising a hydrolyzate of an epoxy-containing silicon compound, at least one member of the group of hydrolyzates of organic silicon compounds, colloidal silica and organic titania compounds, and a curing catalyst.
U.S. Pat. Nos. 4,500,669 and 4,571,365 to Ashlock et al disclose transparent, abrasion-resistant coating compositions comprising a colloidal dispersion of a water-insoluble dispersant in a water-alcohol solution of the partial condensate of silanol wherein the dispersant comprises metals, alloys, salts, oxides and hydroxides thereof.
In the Journal of Non-Crystalline Solids, Vol. 63, (1984), Philipp et al disclose in "New Material for Contact Lenses Prepared From Si- and Ti-Alkoxides by the Sol-Gel Process" that it is possible to combine inorganic and organic elements to develop materials with special properties.
U.S. application Ser. No. 07/440,845 filed Nov. 24, 1989 now U.S. Pat. No. 5,231,156 by Lin discloses organic-inorganic hybrid polymers prepared by polymerizing an organic monomer in the presence of an inorganic oxide sol comprising an organoalkoxysilane having an organic functional group capable of reacting with said organic monomer.